Get a good-fitting saddle for great tone!
These special files fit into standard 3/32" and 1/8" acoustic guitar bridge saddle slots, to clean and flatten the bottom. This gives you uniform contact with the bottom of the saddle for best sound (a critical requirement for undersaddle transducer pickups).
Each 1-15/16" x 13/16" (50mm x 20mm) steel file has fine-cut teeth on the long flat edges, plus smooth sides and rounded ends that won't damage the walls of the slot. The 1/8" file is handy for Fender-style nut slots, too.